I could not get the Phant to work on a Sparkfun Photon Redboard, and discovered I had to make a change to the HTTP POSTing code. I discovered the POSTing logic suggested by Sparkfun in their official Particle Phant wrapper is different from the example code in Sparkfun_Photon_Weather_Phant. Precisely, you want the code in postToPhant to look like

hi – I had the usual problems getting this thing to talk to a “real computer” so i wrote up my steps and posted all the code I used. More or less, I run a tiny stub piece of code on an Atmel that listens to its UART over 9600bps and sends commands to a connected backpack over SPI. This lets me then control the matrix from almost anything at a pretty good FPS without any complications. Here it all is, enjoy:

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